DESIGN ASSURANCE
FOR ENGINEERS
AND
MANAGERS
MECHANICAL
ENGINEERING
A Series
of
Textbooks
and
Reference Books
EDITORS
L. L. FAULKNER
Department
of
Mechanical Engineering
The Ohio State University
Columbus, Ohio
S.
B.
MENKES
Department
of
Mechanical Engineering
The City College
of
the
City University
of
New
York
New
York,
New
York
1.
Spring Designer's Handbook,
by
Harold Carlson
2.
Computer-Aided Graphics
and
Design,
by
Daniel
L.
Ryan
3. Lubrication Fundamentals,
by
J.
George
Wills
4. Solar Engineering for Domestic Buildings,
by
William
A. Himmelman
5.
Applied Engineering Mechanics: Statics and Dynamics,
by
G.
Boothroyd
and
C.
Poli
6. Centrifugal Pump Clinic,
by
Igor
J.
Karassik
7.
Computer-Aided Kinetics for Machine Design,
by
Daniel L.
Ryan
8.
Plastics Products Design Handbook, Part
A:
Materials
and Components; Part
B:
Processes
and
Design for
Processes,
edited
by
Edward Miller
9.
Turbomachinery: Basic Theory and Applications,
by
Earl Logan,
Jr.
10. Vibrations
of
Shells
and
Plates,
by
Werner Soedel
11. Flat and Corrugated Diaphragm Design Handbook,
by
Mario
Di Giovanni
12. Practical Stress Analysis in Engineering Design,
by
Alexander Blake
13. An
Introduction
to
the
Design and Behavior
of
Bolted Joints,
by
John H Bickford
14. Optimal Engineering Design: Principles and Applications,
by
James
N.
Siddall
15. Spring Manufacturing Handbook,
by
Harold Carlson
16. Industrial Noise Control: Fundamentals and Applications,
edited
by
Lewis
H.
Bell
17. Gears and Their Vibration: A
Basic
Approach
to
Understanding
Gear Noise,
by
J.
Derek Smith
18. Chains for Power Transmission and Material Handling: Design
and Applications Handbook,
by
the American Chain Association
19. Corrosion and Corrosion Protection Handbook, edited
by
Philip A. Schweitzer
20. Gear Drive Systems: Design and Application,
by
Peter Lynwander
21. Controlling In-Plant Airborne Contaminants: Systems Design and
Calculations,
by
John
D.
Constance
22. CAD/CAM Systems Planning and Implementation,
by
Charles
S.
Knox
23. Probabilistic Engineering Design: Principles and Applications,
by
James N Siddall
24. Traction Drives: Selection and Application,
by
Frederick
W.
Heilich III
and Eugene
E.
Shube
25. Finite Element Methods:
An
Introduction,
by
Ronald
L.
Huston
and Chris
E.
Passerello
26. Mechanical Fastening
of
Plastics:
An
Engineering Handbook,
by
Brayton Lincoln, Kenneth
J.
Gomes, and James
F.
Braden
27. Lubrication in Practice, Second Edition, edited
by
W.
S.
Robertson
28. Principles
of
Automated Drafting,
by
Daniel
L.
Ryan
29. Practical Seal Design, edited
by
Leonard
J.
Martini
30. Engineering Documentation
for
CAD/CAM Applications,
by
Charles
S.
Knox
31. Design Dimensioning with Computer Graphics Applications,
by
Jerome
C.
Lange
32. Mechanism Analysis: Simplified Graphical and Analytical Techniques,
by
Lyndon
0.
Barton
33.
CAD/CAM
Systems: Justification, Implementation, Productivity Measure-
ment,
by
Edward
J.
Preston, George
W.
Crawford, and Mark
E.
Coticchia
34. Steam Plant Calculations Manual,
by
V.
Ganapathy
35. Design Assurance for Engineers and Managers,
by
John
A.
Burgess
OTHER VOLUMES IN PREPARATION
DESIGN ASSURANCE
FOR
ENGINEERS
AND
MANAGERS
John A. Burgess
Westinghouse Electric Corporation
Power Transformer Plant
Muncie, Indiana
0
~'~~,~~:~~.
Boca
Raton
London New
York
CRC
Press
is
an
imprint
of
the
Taylor
& Francis Group, an informa business
Library
of
Congress
Cataloging
in
Publication
Data
Burgess,
John
A.,
[date]
Design
assurance
for
engineers
and
managers.
(Mechanical
engineering
; 35)
Bibliography:
p.
Includes
index.
1.
Engineering
design.
2.
Reliability
(Engineering)
I.
Title.
II.
Series.
TA174.B87
1984
620'.00425
84-20047
ISBN
0-8247-7258-X
COPYRIGHT
© 1984
by
MARCEL DEKKER
ALL
RIGHTS
RESERVED
Neither
this
book
nor
any
part
may
be
reproduced
or
transmitted
in
any
form
or
by
any
means,
electronic
or
mechanical,
including
photo-
copying,
microfilming,
and
recording,
or
by
any
information
storage
and
retrieval
system,
without
permission
in
writing
from
the
publisher.
MARCEL DEKKER
270
Madison
Avenue,
New
York,
New
York
10016
Current
printing
(last
digit):
10 9 8 7 6
CRC Press
6000 Broken Sound Parkway, NW
Suite 300, Boca Raton, FL 33487
270 Madison Avenue
New York, NY 10016
2 Park Square, Milton Park
Abingdon, Oxon OX14 4RN, UK
Reprinted 2009 by CRC Press
To
my
wife,
Alma
Preface
People
in
industry
and
government
have
long
recognized
the
major
im-
pact
that
design
has
on
products
and
their
usefulness.
Yet,
in
many
cases,
only
limited
attention
is
given
to
the
quality
of
the
design
effort.
It
is
often
just
assumed
that
the
engineering
work
is
good.
Even
though
much
has
been
written
about
quality
control,
nearly
all
of
it
has
been
directed
towards
manufacturing
and
production.
Little
has
been
written
about
the
application
of
quality
methods
to
engineering
activities.
This
book
is
written
for
engineers
and
managers
everywhere
who
want
to
achieve
high
levels
of
quality
in
their
design
work.
It
describes
the
concepts
and
methods
of
a
discipline
called
design
assurance.
The
book
will
also
be
useful
to
quality
assurance
professionals
who
have
al-
ways
wanted
to
know
more
about
the
engineering
process
but
were
afraid
to
ask.
There
is
another
audience
for
this
book,
too.
It
can
be
used
as
supplemental
reading
for
graduate
and
undergraduate
engineering
stu-
dents.
It
reveals
many
nontechnical
aspects
that
are
necessary
for
getting
the
work
done
in
an
engineering
department.
Typically,
these
matters
come
as
a
surprise
to
the
new
graduate.
Accordingly,
this
book
can
aid
in
the
transition
from
student
to
practicing
engineer.
Although
this
book
describes
several
concepts
that
may
be
new
to
the
reader,
it
presents
them
in
ways
engineers
can
use
them
in
their
daily
activities.
The
various
chapters
contain
recommendations,
exam-
ples,
and
preferred
practices
that
illustrate
how
the
concepts
can
be
applied
to
many
products
and
many
industries.
The
methods
presented
in
this
book
typically
provide
a
series
of
checks
and
balances
in
the
engineering
process.
Most
of
these
are
accomplished
within
the
engi-
neering
department
itself.
In
fact,
some
readers
will
simply
consider
these
methods
as
"good
engineering
practices.
"
The
contents
of
this
book
are
based
largely
on
the
author's
obser-
vations
and
experiences
with
many
companies
over
the
past
30
years.
Having
worked
as
an
engineer
and
manager
in
several
engineering
and
quality
assurance
departments,
I
have
seen
these
practices
from
both
v
vi
Preface
vantage
points.
Some
of
the
techniques
are
well
known
and
widely
recog-
nized.
Others
are
more
subtle
and
less
visible
to
the
casual
observer.
However,
collectively,
they
represent
a
substantial
part
of
that
body
of
knowledge
known
as
design
assurance.
The
value
of
such
methods
comes
in
their
application.
Yet,
as
they
say,
there
is
more
than
one
way
to
skin
the
cat.
I
encourage
the
readers
to
experiment
with
these
techniques.
Modify
them
to
fit
your
local
situ-
ation,
but,
above
all,
give
them
a
try.
As
you
can
imagine,
a
book
like
this
doesn't
happen
overnight.
The
concepts
grow
from
ideas
and
events
over
a
long
period
of
time.
I
owe
much
to
my
compatriots
at
Westinghouse
for
their
knowledge,
imagination,
and
persistence
in
developing,
honing,
and
applying
many
of
the
tools
and
techniques
discussed
in
this
book.
Special
thanks
go
to
several
who
have
had
far
greater
influence
on
me
than
they
would
ever
have
guessed.
These
include
Joe
Kenney,
Frank
Retallick,
Joe
Gallagher,
Rod
Jones,
Ed
Kreh,
Fred
Henning,
Lyle
Connell,
Nate
Moore,
Ralph
Barra,
F.
X.
Brown,
and
Bernie
Hyland.
I
also
want
to
thank
Jack
Martin
from
the
Westinghouse
Muncie
Plant
for
his
excellent
assistance
in
obtaining
the
various
illustrations
used
throughout
the
book.
And,
finally,
I
am
deeply
grateful
for
the
fine
typing
support
I
received
from
Kathy
Reynard,
Sally
Taylor,
Cindy
Mills,
and
Cindy
Dorste
at
the
Westinghouse
Plant.
It
is
my
hope
that
this
book
will
be
helpful
to
engineers
and
their
managers
in
understanding
and
using
design
assurance
techniques.
It
is
a
process
which
contributes
to
the
creation
of
conditions
for
excellence
in
engineering.
For
in
the
long
run,
it
will
take
excellence,
and
nothing
less,
to
meet
t'he
challenges
of
the
complex
and
ever-changing
world
we
live
in.
John
A.
Burgess
Contents
Preface
v
1.
Introduction
to
Design
Assurance
1
1.1
The
Evolution
of
Controlling
Product
Quality
1
1. 2
The
Concept
of
Design
Assurance
2
1. 3
The
Role
of
Engineering
Management
5
1. 4
Relationships
with
Other
Disciplines
8
1.
5
Starting
a
Design
Assurance
Program
10
1.
6
Summary
15
2.
Design
Requirements
16
2. 1
Introduction
16
2. 2
External
Sources
of
Requirements
18
2. 3
Internal
Sources
20
2. 4
Functional
Analysis
22
2. 5
Translation
of
Requirements
into
Designs
27
2.6
Summary
31
3.
Drawing
Control
32
3. 1
Introduction
33
3.
2
Types
of
Drawings
33
3. 3
Drawing
Preparation
46
3. 4
Drawing
Review
and
Approval
50
3. 5
Drawing
Document
Control
53
3. 6
Drawing
Revisions
57
3. 7
Summary
62
4.
Specification
Control
63
4.
1
Introduction
63
4. 2
Types
of
Specifications
64
4. 3
Specification
Preparation
72
4. 4
Specification
Review
and
Approval
76
vii
viii
Contents
4. 5
Specification
Document
Control
78
4.
6
Specification
Revisions
81
4. 7
Summary
83
5.
Configuration
Control
84
5.
1
Introduction
84
5. 2
Configuration Identification
86
5.
3
Control
of
Changes
90
5.
4
Configuration
Verification
102
5.
5
Summary
103
6.
Design
Methods
and
Analysis
104
6.1
Introduction
104
6.2
Design
Methods
105
6.3
Design
Analysis
114
6.4
Design
Integration
122
6.5
Summary
122
7.
Control
of
Engineering
Software
124
7
.1
Introduction
125
7.
2
Software
Design
128
7. 3
Coding
and
Debugging
Computer
Programs
132
7.
4
Program
Verification
138
7. 5
Documentation
and
Control
of
Computer
Programs
141
7. 6
Summary
149
8.
Product
Testing
151
8.1
Introduction
151
8.2
Initiating
the
Test
155
8.3
Performing
the
Test
159
8.4
Reporting
Results
161
8.5
Summary
165
9.
Design
Reviews
166
9.1
Introduction
166
9.
2
Formal
Design
Reviews
167
9.
3
Requirements
Review
179
9.
4
Design
Verification
Reviews
179
9.
5
Informal
Design
Reviews
181
9.
6
An
Integrated
Approach
181
9.
7
Summary
182
10.
Statistical
Tools
for
Design
Assurance
183
10.1
Introduction
183
10.
2
Frequency
Distributions
184
10. 3
The
Normal
Curve
188
10.
4
Process
Capability
192
Contents
ix
10.
5
Statistical
Tolerancing
195
10.6
Summary
197
11.
Control
of
Nonconformances
198
11.1
Principles
of
Control
198
11.
2
Nonconformance
Reporting
201
11.
3
Disposition
of
Non
conformances
203
11.
4
Closeout
and
Feedback
204
11.
5
Summary
205
12.
Engineering
Records
207
12.1
Introduction
207
12.2
Methods
for
Indexing
208
12.3
Filing
Practices
211
12.4
Records
Retention
218
12.5
Summary
220
13.
Supporting
Documentaticm
221
13.1
Introduction
221
13.
2
Operation
and
Maintenance
Instructions
222
13.
3
Replacement
Parts
Lists
228
13.
4
Design
Control
Measure~
231
13.
5
Summary
232
14.
Reliability
Improvement
233
14.
1
Introduction
233
14.
2
Reliability
Reporting
System
235
14.
3
Measuring
and
Analyzing
Product
Reliability
238
14.
4
Reliability
Design
Tools
244
14.
5
Reliability
Testing
254
14.
6
Reliability
Assessment
256
14.
7
Summary
257
15.
Auditing
the
Engineering
Process
259
15.
1
Introduction
260
15.
2
Fundamentals
of
Systems
Auditing
260
15.3
Areas
for
Investigation
267
15.
4
Ethics
of
Auditor
Conduct
270
15.
5
Improving
the
System
272
15.
6
Summary
274
16.
Design
Assurance
in
the
Future
275
16.
1
Engineering
Management
Responsibilities
276
16.
2
Drawings
276
16.
3
Specifications
277
16.
4
Configuration
Control
277
16.
5
Design
Methods
and
Analysis
277
16.
6
Engineering
Software
278
x
Contents
16.7
Product
Testing
278
16.8
Design
Reviews
278
16.9
Statistical
Tools
278
16.10
Control
of
Nonconformances
279
16.11
Engineering
Records
and
Supporting
Documentation
279
16.12
Reliability
Improvements
279
16.13
Conclusions
280
Appendixes
Appendix
1:
Equipment
Specification
Contents
283
Appendix
2:
Sample
Design
Review
Checklist
287
Appendix
3:
Guidelines
for
Auditing
the
Engineering
Function
289
Selected
Readings
291
Index
297
DESIGN ASSURANCE
FOR ENGINEERS
AND
MANAGERS
1
Introduction to Design Assurance
1.1
The
Evolution
of
Controlling
Product
Quality
1
1.
2
The
Concept
of
Design
Assurance
2
1.
3
The
Role
of
Engineering
Management
5
1.
3.1
Setting
Policy
5
1.
3.
2
Giving
Direction
7
1.
3.
3
Provide
for
Training
7
1.
3.4
Monitor
and
Evaluate
Results
7
1.3.5
Maintain
the
Pursuit
of
Excellence
7
1.
4
Relationships
with
Other
Disciplines
8
1.4.1
Marketing
and
Engineering
8
1.4.
2
Purchasing
and
Engineering
9
1.
4. 3
Manufacturing
and
Engineering
9
1.
4. 4
Quality
Assurance
and
Engineering
10
1.4.
5
Accounting
and
Engineering
10
1.
5
Starting
a
Design
Assurance
Program
10
1.5.1
Self-
Examination
11
1.
5.
2
Think
Big,
Start
Small
14
1.
5.3
Follow-On
Activities
15
1.6
Summary
15
1. 1
THE
EVOLUTION
OF
CONTROLLING
PRODUCT
QUALITY
For
many
years
the
control
of
product
quality
was
considered
a
factory
responsibility.
It
was
largely
a
process
of
inspection-try
to
find
the
bad
ones
and
separate
them
from
the
good
ones.
However,
as
mass
production
expanded,
people
began
to
realize
the
costs
and
inefficien-
cies
of
this
approach
were
very
high.
2
Introduction
to
Design
Assurance
This
awareness
gave
birth
to
a
new
and
broader
outlook
on
the
management
of
product
quality.
Shortly
after
World War
II
various
specialists
in
the
quality
control
field
developed
the
concept
of
Total
Quality
Control.
It
is
based
on
the
premise
that
quality
must
be
con-
sidered
and
factored
into
every
aspect
of
the
product-from
design
through
production
and
delivery.
Under
this
approach,
all
facets
of
a
business
are
integrated
to
achieve
the
desired
levels
of
quality.
One
of
the
major
contributions
of
the
Total
Quality
Concept
is
the
recognition
of
the
importance
of
preventing
defects
from
happening.
The
old
adage,
"An
ounce
of
prevention
is
worth
a
pound
of
cure,"
is
especially
applicable
to
modern
industry.
Detecting
non-conforming
or
defective
products
is
a
difficult
and
expensive
process.
Even
then,
it
is
often
only
marginally
successful.
A
far
better
approach
is
to
prevent
the
defects
from
occurring
initially.
This
approach
includes
having
the
right
requirements
and
the
proper
design
as
well
as
seeing
the
product
is
manufactured
correctly.
In
addition
to
the
Total
Quality
Control
concept,
other
means
for
enhancing
the
quality
and
effectiveness
of
product
design
have
been
developed
over
the
past
several
decades.
One
notable
effort
has
been
cultivated
by
the
American
Society
of
Mechanical
Engineers.
In
the
1920s
and
1930s
each
boiler
manufacturer
designed
and
built
his
product
according
to
their
own
methods
and
practices.
Periodically,
this
resulted
in
boiler
failures
which
caused
extensive
damage
and
loss
of
life.
Finally
a
small
group
of
engineers
affiliated
with
ASME
took
it
upon
themselves
to
develop
a
standard
set
of
rules
and
practices
for
all
manufacturers
to
use.
This
led
to
safer
designs,
and
the
approach
has
been
very
successful
through
the
years
in
dramatically
reducing
boiler
and
pressure
vessel
failures.
Many
techniques
are
now
being
applied
in
industry
to
prevent
defects
from
occurring
in
design
and
production.
This
focus
on
pre-
vention
has
been
a
major
contributing
factor
in
the
evolution
of
design
assurance.
1. 2
THE
CONCEPT
OF
DESIGN
ASSURANCE
Design
Assurance,
also
referred
to
as
Design
Control,
is
a
relatively
new
term
in
our
industrial
vocabulary.
It
has
developed
slowly
from
Drawing
Control
and
expanded
to
cover
all
facets
of
product
engineer-
ing
activities.
For
the
purposes
of
this
book,
Design
Assurance
is
defined
as:
...
those
planned
and
systematic
actions
taken
to
provide
con-
fidence
that
the
product
design
will
satisfy
the
requirements
of
its
intended
use.
The
Concept
of
Design
Assurance
It
is
a
response
to
the
rapid
advances
in
technology,
increased
complexity
and
growing
sophistication
in
industry.
No
longer
is
it
acceptable
to
rely
on
the
"business-as-usual"
methods
and
practices
of
years
gone
by.
The
Design
Assurance
process
is
an
outgrowth
of
management
methods
developed
and
used
on
military,
aerospace
and
nuclear
pro-
jects.
Various
quality
systems
were
developed
in
the
1960s
and
1970s
3
to
manage
the
process
of
achieving
the
proper
levels
of
quality.
Exam-
ples
of
these
include
MIL-Q-9858A, NASA
NHB
5300.3,
AEC-10CFR50
Appendix
B,
and
ASME/ANSI NQA-1.
Each
of
these
program
require-
ments
documents
contained
provisions
for
controlling
engineering
activities.
Understandably,
the
application
of
special
quality
system
require-
ments
on
engineering
activities
came
as
quite
a
surprise
to
manypeople.
Always
before,
quality
control
focused
only
on
the
factory.
Yet
under
closer
examination,
experienced
engineers
and
technical
mangers
will
recognize
that
most
of
the
elements
of
Design
Assurance
are
simply
good
engineering
practices.
Why
then
all
the
fanfare
about
some
new
discipline
called
Design
Assurance?
The
best
way
to
answer
that
question
is
with
some
real-
life
examples.
During
the
construction
of
a
large
nuclear
powerplant,
a
major
earthquake
fault
was
discovered
a few miles
away
from
the
powerplant
site.
After
much
investigation
and
analysis,
it
was
concluded
that
additional
seismic
supports
were
required.
The
owner
of
the
power-
plant
hired
a
competent
engineering
firm
to
do
the
redesign.
The
owner
furnished
a
sketch
of
the
plant
arrangement
which
was
to
be
used
in
the
design
project.
However
the
sketch
was
"very
sketchy."
It
did
not
contain
all
of
the
information
that
was
required
and,
in
fact,
was
based
on
some
outdated
drawings.
However,
the
design
group
believed
they
had
the
correct
information
that
was
needed.
As a
re-
sult,
the
design
work
was
accomplished,
but
it
was
not
usable
because
it
was
based
on
incorrect
input.
After
the
design
work
was
finally
corrected,
the
owner
asked
that
the
new
design
be
applied
to
the
adjacent,
companion
unit.
However,
the
owner
failed
to
tell
that
the
companion
unit
was
not
identical
to
the
first,
but
was
a
mirror
image
of
it.
Again
the
results
were
not
usable
until
further
corrections
were
made.
A
medium-sized
manufacturing
firm
produced
a
line
of
single
and
multi-stage
pumps
and
enjoyed
a
strong
market
position
in
their
in-
dustry.
To
the
management's
delight,
they
received
a
very
large
order
for
their
pumps.
However,
the
application
required
some
development
and
modification
of
the
standard
designs.
During
the
development
phase,
the
engineers
made a
series
of
changes
to
the
internal
config-
uration.
However,
when
the
first
new
pumps
went
into
production,
4
Introduction
to
Assurance
several
of
the
impellers
cracked
and
broke
during
acceptance
testing.
After
a
detailed
investigation,
it
was
found
that
the
structural
analysis
was
performed
on
the
next-to-last
revision,
but
not
on
the
final
change.
The
last
modifications
caused
the
structural
limits
to
be
exceeded,
but
no
one
realized
the
shortcoming
until
the
pumps
failed
mechanically,
Another
firm
entered
the
microprocessor-controlled
equipment
area
after
many
years
of
success
as
a
builder
of
hydromechanically
controlled
equipment.
Although
the
design
and
development
efforts
proceeded
cautiously,
the
overall
knowledge
and
skill
of
the
design
force
was
limited
in
the
field
of
electronic
controls.
Considerable
time
and
money
was
wasted
as
a
result
of
inadequate
technical
review
of
the
design.
Many
errors
and
oversights
were
made
on
matters
which
otherwise
would
have
been
found
and
corrected
by
qualified
electronics
designers.
Finally,
the
management
realized
the
shortcomings
and
obtained
the
nec-
essary
expertise
for
the
program,
and
just
in
time
to
prevent
a
total
disaster.
Now,
to
answer
the
earlier
question:
Why
all
the
fanfare
about
Design
Assurance?
It
is
in
recognition
of
the
major
impact
that
design
has
on
the
long-range
well-being
of
a
project,
a
product,
or
a
producer.
Today's
consumers
are
much
more
aware
of,
and
concerned
about,
the
quality
of
the
products
they
buy
and
use.
Management
now
is
realizing
it
is
very
difficult
and
costly
to
try
to
make
a
good
product
out
of
a
poor
design.
Errors
or
shortcomings
in
design
are
often
hidden
until
the
design
becomes
hardware.
Even
then,
design
problems
may
not
show
up
until
many
units
have
been
produced
and
are
in
operation.
When a
problem
is
discovered
at
this
stage,
it
may
be
both
expensive
and
embarrassing
to
correct.
Yet,
the
penalties
of
the
marketplace,
and
more
recently
of
the
courts,
for
failing
to
correct
a
problem,
may
be
even
worse.
Design
Assurance
is
a
response
to
these
conditions.
It
is
another
management
tool
for
running
the
business
in
an
efficient
and
effective
manner.
And
it
should
be
management's
responsibility.
Several
years
ago,
Dr.
Juran,
a
prominent
authority
in
the
field
of
quality,
found
in
his
studies
of
industrial
problems,
that
the
workers
cause
or
can
correct
only
about
20%
of
the
quality
problems,
The
remaining
80%
of
the
problems
are
caused
by
management,
or
are
within
their
ability
to
in-
fluence
or
control.
Design
Assurance
is
also
a
direct
response
to
the
need
for
defect
prevention.
Instead
of
allowing
the
product
to
get
into
production
and
then
seeing
if
it
will
work,
it
is
an
approach
for
anticipating
what
can
go
wrong
and
preventing
it
from
occurring.
This
also
includes
examin-
ing
past
designs
and
their
problems
and
taking
action
for
preventing
recurrence
of
the
old
problems
in
the
new
designs.
Do
it
right
the
first
time
is
the
theme
of
Design
Assurance.
Design
Assurance
covers
many
traditional
areas
of
engineering,
such
as
drawing
and
specification
control,
but
it
also
includes
broader
facets,
such
as,
a
disciplined
approach
to
design
decisions,
verifica-
tion
of
design
adequacy,
control
of
engineering
software,
proper
The
Role
of
Engineering
Management
5
integration
of
interfacing
designs
and
design
activities,
and
the
inter-
action
of
product
feedback
with
the
design
process.
As
the
state
of
the
art
of
technology
advances
and
the
complexity
of
products
and
systems
increases,
it
is
no
longer
possible
to
rely
on
the
handbooks
of
old
and
the
seat-of-the-pants
method
of
engineering
Ii
product.
Greater
emphasis
must
be
placed
on
a
more
disciplined,
but
man-
ageable,
approach
to
engineering
than
has
been
used
in
many
indus-
tries.
Yet,
the
process
must
not
be
so
rigid
or
overbearing
that
it
stifles
creativity
or
ingenuity.
Also
it
must
be
responsive
to
cost
and
time
demands
to
be
competitive
and
to
the
resource
limitations
of
the
firm.
Obviously,
these
are
challenging
criteria
to
be
met
by
engineers
and
their
managers.
And
meet
it
they
must.
The
subsequent
portions
of
this
book
are
intended
to
help
those
same
persons
with
suggestions
and
recommendations
on
how
to
accom-
plish
that
feat.
1. 3
THE
ROLE
OF
ENGINEERING
MANAGEMENT
Engineering
management
must
take
the
lead
in
the
introduction,
devel-
opment,
implementation
and
maintenance
of
the
Design
Assurance
pro-
gram.
It
is
not
something
that
naturally
grows
from
the
bottom
up.
It
requires
imagination,
leadership
and
fortitude
to
make
it
happen
and
do
it
without
mutiny
or
malpractice.
Engineering
management
sets
the
tone
for
the
engineering
organi-
zation
in
its
attitude
and
actions
on
matters
involving
engineering
excellence.
How
does
the
engineering
manager
respond
when
faced
with
a
surprise
problem?
A
conflict
between
a
marketing
requirement
and
a
preferred
design
practice?
A
choice
between
cost
and
quality?
How
high
is
his
tolerance
for
errors?
Decisions
and
actions
on
these
and
similar
situations
influence
the
engineering
organization's
attitude
toward
the
pursuit
of
excellence
in
their
work.
Each
engineering
man-
ager
needs
to
reflect
on
their
own
actions.
Do
your
actions
match
your
words?
1. 3. 1
Setting
Policy
Establishing
policies
for
assuring
the
quality
of
design
is
Engineering
management's
responsibility.
These
policies
need
to
be
written
for
all
to
see
and
use
in
the
day-to-day
decision-making
process.
A
policy
statement
need
not
be
written
in
the
poet's
prose
or
in
lengthy
text.
In
fact,
the
most
effective
policies
tend
to
be
brief
and
to
the
point.
One
such
policy
statement
is
shown
in
Figure
1.1.
It
is
for
a
company
deeply
involved
in
high
technology
and
major
technical
systems.
In
contrast,
the
policy
statement
presented
in
Figure
1.
2
is
for
a
relative-
ly
small firm
which
operates
in
a
specialty
product
niche.
This
com-
pany
works
with
relatively
conventional
and
straightforward
products
and
problems.
6
Introduction
to
Design
Assurance
DESIGN
ASSURANCE
POLICY
It
is
the
policy
of
the
Engineering
Department
to
strive
for
excellence
in
all
of
its
efforts
related
to
design
and
development
of
products
for
our
customers.
Engineering
management
is
dedicated
to
employ
only
persons
of
vision,
skill
and
integrity
and
to
provide
them
with
the
tools,
facilities
and
resources
to
perform
their
work
with
precision
and
accuracy.
Engineered
products
shall
be
designed
in
strict
accordance
with
the
applicable
codes,
standards
and
specifications.
Each
new
design
shall
be
thoroughly
evaluated
and
proven,
using
the
latest
methods
and
practices
available,
prior
to
releasing
it
for
operational
use.
In
the
event
that
defects
or
discrepancies
are
identified,
appro-
priate
corrective
actions
shall
be
taken
promptly
to
correct
the
prob-
lem,
and
measures
shall
be
implemented
to
prevent
future
recurrence
of
the
conditions
adverse
to
quality.
Fl GURE
1.
1
Sample
policy
statement
for
a
high-technology
company.
DESIGN
POLICY
The
Engineering
Department
shall
exercise
care
and
concern
in
the
design
of
the
company's
products.
Appropriate
methods
shall
be
used
to
assure
the
designs
meet
the
performance,
reliability,
cost
and
safe-
ty
requirements
while
providing
products
our
customers
consider
to
be
of
value
to
them.
Each
person
is
expected
to
perform
their
work
accu-
rately
in
accordance
with
the
proper
methods
and
to
report
to
manage-
ment
any
instances
where
errors
or
discrepancies
are
found.
FIGURE
1.2
Sample
policy
statement
of
a
company
with
simple
products.
The
Role
of
Engineering
Management
7
Such
policy
statements
frame
the
concepts
of
design
assurance
as
they
are
to
be
applied
by
those
particular
companies.
The
policy
becomes
the
foundation
for
the
building
of
the
design
assurance
structure.
And,
of
course,
it
serves
as
an
important
yardstick;
it
continually
raises
the
question:
How
are
we
measuring
up?
I.
3. 2
Giving
Direction
But
policy
alone
is
not
enough.
It
needs
to
be
converted
into
direc-
tion
and
action.
Engineering
management
must
provide
the
leader-
ship
to
get
the
program
functioning.
They
must
see
to
it
that
the
necessary
resources
are
applied
to
develop
applicable
methods
and
procedures.
For
without
these,
the
program
is
simply
a
figment
of
the
imagination.
The
methods
and
procedures
must
address
the
details
of
how
the
work
is
to
be
performed.
Answers
to
those
basic
questions
of:
What?
When? Where? Why?
and
Who?
need
to
be
answered
according
to
local
needs.
It
takes
time,
thought
and
a
bit
of
trial-and-error
to
come
up
with
workable
procedures.
So
don't
be
discouraged
if
the
first
cut
seems
awkward
or
only
partially
successful.
Engineers
rely
heavily
on
the
iterative
process
to
perfect
their
designs.
The
same
process
applies
equally
well
to
the
development
of
their
administra-
tive
procedures.
1.
3. 3
Provide
for
Training
Once
the
methods
are
developed,
management
must
make
provisions
for
training
the
affected
persons
and
groups
to
use
the
new
methods.
It
does
not
have
to
be
an
elaborate
program.
Simply
concentrate
on
two
key
points:
(1)
How
you
want
the
work
performed?
and
(2)
Why
it
is
important
to
do
it
this
way?
Answers
to
both
questions
are
nec-
essary
to
achieve
the
desired
results.
1. 3. 4
Monitor
and
Evaluate
Results
Engineering
management
also
must
take
the
time
periodically
to
monitor
the
progress
and
evaluate
the
results.
Is
the
work
really
being
done
in
the
desired
manner?
Are
we
getting
the
expected
results?
Is
it
being
accomplished
in
a
timely
and
cost-effective
manner?
These
are
questions
that
management
needs
to
ask
and
to
get
answered.
Later
in
the
book,
guidelines
and
instructions
for
auditing
the
engineering
activities
are
described
(see
Chapter
15).
This
approach
is
an
effective
means
of
gathering
data
for
the
evaluation
process.
1. 3. 5 Maintain
the
Pursuit
of
Excellence
To
get
the
maximum
benefit
from a
design
assurance
program,
it
must
become
an
integral
way
of
life.
It
can
not
be
like
a
fancy
coat
you
put
on
for
show
on
special
occasions
and
then
put
back
in
the
closet
8
Introduction
to
Design
Assurance
after
the
event
is
over.
Design
assurance
needs
to
be
an
active
and
on-going
part
of
business.
It
is
a
tool
for
all
to
use
in
the
pursuit
of
excellence
in
engineering.
Excellence
is
used
in
the
sense
of
value-a
product
or
service
which
the
customer
considers
is
particularly
useful
and
at
a
price
which
the
buyer
finds
especially
attractive.
Words
such
as
"dependable,"
"reliable,"
"trouble-free,"
"the
best,"
are
often
used
by
customers
in
describing
their
personal
understanding
of
value
and
excellence.
As
part
of
this
effort
for
achieving
excellence,
Engineering
man-
agement
must
be
actively
involved
in
preventing
defects.
This
re-
quires
an
on-going
commitment
for
improving
the
quality
of
design
through
corrective
actions.
In
the
heat
of
battle
it
is
common
to
cove1
an
injury
with
a
band-aid.
But
in
the
long
run,
major
surgery
may
be
required
to
repair
the
damage
or
cure
the
disease.
It
takes
both
courage
and
commitment
to
eliminate
causes
and
not
simply
treat
symp-
toms.
Consequently,
engineering
management
must
face
those
decis-
ions
squarely.
They
are
expected
to
take
the
steps
needed
to
prevent
design
problems
from
inflicting
serious
wounds
on
the
company.
Per-
sonal
pride,
NIH
factors,
inventor's
attachment
and
"ivory-tower"
isolation
are
stumbling
blocks
along
the
path.
Regardless
of
these
difficulties,
enlightened
management
is
obligated
to
press
ahead
to
achieve
quality
in
design.
The
pursuit
of
excellence
is
a
never-ending
journey.
1.4
RELATIONSHIPS
WITH
OTHER
DISCIPLINES
Engineering
typically
enjoys
an
element
of
respect
from
other
depart-
ments
due
to
the
specialty
knowledge
and
skills
and
from
its
tradition-
al
role
as
the
decision
maker
on
technical
matters.
However,
some
engineering
departments
also
are
viewed
with
a
certain
element
of
dis-
respect.
This
may
be
due
to
past
actions
which
seem
to
say
to
others
that
Engineering
is
"too
good
to
get
their
hands
dirty
in
the
daily
problems."
Unfortunately,
respect
can
only
be
earned
and
not
legislated.
Engineering's
role
is
typically
such
that
they
influence
nearly
all
other
groups
and
functions.
Thus,
Engineering
cannot
be
an
island
unto
itself.
And
for
a
company
to
reap
the
benefits
of
profitability,
high
productivity,
customer
credibility,
and
workforce
pride
that
a
Total
Quality
Commitment
can
offer,
Engineering
must
be
an
active
and
responsive
member
of
the
team.
Again,
the
leadership
and
direction
must
come from
Engineering
management.
Let's
look
at
several
of
the
relationships
Engineering
needs
to
cultivate
within
the
company
as
part
of
its
development
of
a
design
assurance
program.
1. 4. 1
Marketing
and
Engineering
To
obtain
the
maximum
favorable
impact
from
the
design
assurance
Relationships
with
Other
Disciplines
9
program,
Engineering
needs
to
work
closely
with
Marketing.
Details
of
customer
requirements,
market
trends,
competitors'
actions
and
products,
and
feedback
on
the
company's
product
performance
are
important
inputs
to
the
engineering
process.
It
is
imperative
that
the
design
engineer
receives
the
correct
customer
requirements
and
is
ad-
vised
of
market
developments
and
field
problems
in
a
timely
manner.
Conversely,
it
is
equally
important
for
Engineering
to
keep
Mar-
keting
advised
of
promising
new
developments,
the
need
for
design
changes,
the
introduction
of
design
improvements,
etc.
Periodic
meetings
between
the
design
and
sales
groups
are
often
helpful
in
this
regard.
It
takes
this
kind
of
teamwork
to
be
an
effective
competitor.
Also
a
good
Engineering-Marketing
interface
is
crucial.
for
enhancing
the
quality
of
design.
Remember,
it
is
not
enough
to
do
the
design
right;
it
must
be
the
right
design
for
the
market.
And,
unfortunately,
there
are
a
lot
of
well-designed
"buggy
whips"
to
prove
the
point.
1. 4. 2
Purchasing
and
Engineering
It
is
common
to
find
that
30-
50%
of
a
product's
cost
comes from
pur-
chased
material
and
parts.
This
obviously
has
a
major
influence
on
the
finished
product.
To
adequately
control
this
important
element,
Purchasing
and
Engineering
need
to
work
together
closely
in
many
areas.
This
includes:
the
selection
and
qualification
of
suppliers,
a
thorough
and
accurate
definition
of
what
is
wanted,
the
resolution
of
supplier's
questions
and
problems,
and
evaluation
of
the
actual
per-
formance
of
the
parts
and
materials
the
supplier
provides.
Engineer-
ing
must
be
willing
to
investigate
requests
for
changes,
resolve
am-
biguities,
and
occasionally
relax
some
of
the
requirements.
Purchasing
and
Engineering
can
make
major
contributions
in
cost
control,
product
performance
and
timely
resolution
of
problems.
1. 4. 3
Manufacturing
and
Engineering
Although
there
is
a
long-standing
tradition
of
conflict
between
design
and
production,
that
is
a
condition
that
must
be
changed
to
be
suc-
cessful
in
today's
markets.
Otherwise,
the
company
will fall
short
in
its
efforts
to
enhance
the
quality
of
its
designs
and
products.
In
many
instances
the
interface
between
Engineering
and
Manu-
facturing
is
much
like
the
interface
between
Engineering
and
Purchas-
ing.
The
Manufacturing
Department
and
outside
suppliers
have
needs
from
Engineering
that
are
quite
similar,
e.g.
,
clear
and
complete
product
definition,
control
of
changes,
realistic
tolerances,
timely
resolution
of
questions
and
problems,
etc.
From
Engineering's
standpoint,
they
have
every
right
to
expect
Manufacturing's
compliance
routinely
with
realistic
design
requirements.
Many
of
the
basic
elements
of
Design
Assurance
covered
in
subse-
quent
chapters,
such
as
design
and
specification
control,
control
of
10
Introduction
to
Design
Assurance
changes,
and
resolution
of
non-conformances,
are
tightly
interwoven
with
the
Engineering-Manufacturing
interface.
Each
of
these
inter-
actions
provide
an
opportunity
for
teamwork
to
get
the
best
possible
results.
It's
tough
enough
to
fight
the
competition;
don't
make
it
tougher
by
having
a
running
feud
between
Manufacturing
and
Engineering.
1. 4. 4
Quality
Assurance
and
Engineering
The
interface
between
Quality
Assurance
and
Engineering
is
a
natural
one.
Both
are
interested
in
conformance
with
the
requirements
and
with
the
resolution
of
quality
problems.
However,
Engineering
fre-
quently
fails
to
recognize
QA's
need
for
information
and
thorough
understanding
of
design
intent.
Also
design
engineering
underestimates
the
contribution
that
QA's
data
can
make
in
describing
how a
product
or
process
is
really
working.
The
advances
in
technology
make
it
nec-
essary
for
Engineering
and
Quality
Assurance
to
work
hand-in-hand
throughout
the
product
life
cycle,
from
conceptual
design
through
production
and
operation.
It
takes
this
kind
of
interaction
to
gather
and
apply
real-world
data
to
the
company's
designs.
1.4.5
Accounting
and
Engineering
One
interface
that
is
frequently
neglected
is
the
one
between
Account-
ing
(or
Controller)
and
Engineering.
Granted,
many
of
the
tasks
that
the
financial
control
group
performs
have
little
effect
on
the
design
of
the
product.
However,
those
aspects
of
product
cost
accounting
should
and
do
play
an
important
role.
For
effective
design
control,
Engineering
needs
to
know
and
ap-
preciate
how
its
designs
affect
the
cost
of
the
product
and
what
the
impact
of
new
designs
is
on
factory
costs,
inventories,
tooling,
etc.
The
cost
data
can
provide
useful
insights
and
feedback
to
the
Engineering
organization,
and
these
should
not
be
overlooked
in
the
Design
Assurance
effort.
In
fact,
the
increasing
growth
of
inter-
active
design
tools
now
makes
it
more
important
than
ever
to
consider
the
impact
of
cost
as
various
designs
are
considered
and
evaluated.
1. 5
START
I NG A
DESIGN
ASSURANCE
PROGRAM
Before
making
a
big
deal
about
starting
a
new
program
called
Design
Assurance,
the
management
should
recognize
that
some
elements
prob-
ably
are
already
in
place.
Nearly
every
engineering
organization
has
some
methods
it
uses
to
develop
new
products,
to
define
what
the
shop
has
to
make,
and
to
get
information
about
changes
to
at
least
a few
persons
who
need
to
know.
It
is
often
the
degree
or
extent
of
the
process
that
may
need
to
be
revised
or
strengthened.
Starting
a Design
Assurance
Program
It
is
also
quite
possible
that
the
management
and
long-time
pro-
fessionals
may
not
be
familiar
with
the
term
"Design
Assurance"
or
appreciate
what
it
typically
involves.
11
Therefore
the
starting
point
should
be
a
review
of
present
prac-
tices
and
a
comparison
with
various
elements
frequently
found
in
ef-
fective
Design
Assurance
programs.
1.
5.
1
Self-Examination
The
Table
of
Contents
and
the
subsequent
chapters
of
this
book
pre-
sent
the
major
elements
and
recommended
practices
to
apply
in
Design
Assurance
programs.
Obviously,
it
is
desirable
to
read
and
consider
these
elements
carefully
in
preparation
for
the
review
of
the
present
practices
used
locally.
Table
1.1
is
an
abbreviated
compilation
of
key
Design
Assurance
program
elements.
It
is
arranged
in
a
manner
to
suggest
a wide
range
of
possible
coverage.
The
columns
on
the
left
represent
little
or
no
control,
while
the
column
on
the
extreme
right
represents
a
compre-
hensive,
integrated
approach
to
Design
Assurance.
Upon
examination
of
the
local
program,
the
person
or
persons
responsible
for
the
review
may
find
one
or
more
elements
are
performed
in
an
acceptable
manner.
However,
other
elements
may
be
totally
lacking
or
need
strengthening.
When
reviewing
existing
practices,
the
evaluator
needs
to
seek
answers
to
several
key
questions.
These
questions
are:
1. What
are
we
doing
now?
2.
How
well
does
it
work?
3. What
else
needs
to
be
done?
The
questions
should
not
be
answered
lightly.
Some
investigation
of
actual
practices,
results,
recurring
problems,
etc.,
should
be
made.
Don't
simply
assume
everything
is
done
in
the
manner
management
would
like
for
it
to
be
done.
Take
a
first-hand
look.
Check
some
of
the
indicators,
such
as,
the
number
of
changes
being
processed,
vol-
ume
of
shop
requests
for
waivers
or
revisions,
product
failure
rates,
customer
complaints,
drafting
hours
per
drawing
produced,
accounting
charges
for
engineering
errors,
etc.
Be
reasonably
methodical
in
the
investigation.
Look
at
various
elements
and
draw
conclusions
on
what
you
find.
Include
drawings,
specifications,
calculations,
records,
development
tests
and
design
changes
in
your
evaluation.
Which
areas
appear
to
be
satisfactory,
at
least
for
the
time
being?
Which
areas
appear
to
be
sources
of
prob-
lems? Which
areas
aren't
being
addressed
at
all
but
probably
should
be?
Note
which
ones
seem
to
be
satisfactory
and
which
ones
appear
weak.
These
conclusions
should
then
serve
as
the
key
inputs
for
deciding
where
to
start.
TAB
LE
1. 1
The
Evolution
of
Design
Assurance
Design
require-
ments:
Drawing
control:
Control
of
changes:
Engineering
calculations:
No
program
The
designer
figures
out
what'
s
needed.
The
designer
makes
sketches
and
notes
for
the
shop.
Verbal
instructions
from
engineer.
Parts
sized
by
hand-
book
and
seat-of-the-
pants
engineering.
The
salesman
sends
spec
sheets.
Drafting
pre-
pares
drawings
per
designer's
instructions.
Drawings/specs
marked
up
by
engineer.
Engineer
per-
forms
written
calculations
based
on
per-
sonal
methods.
Occasional
meetings
between
Engineer-
ing
and
Sales
man-
agers
to
discuss
new
developments/
marketplace
hap-
penings.
Engineers'
supervisor
reviews
selected
drawings.
Engineer
issues
written
change
notice.
Engineering
calcula-
tions
for
selected
items
reviewed
by
supervisor
or
lead
engineer.
Engineer
and
sales-
man
work
together
on
bid/
contract
reviews.
A few
technical
spe-
cialist's
review
and
sign
selected
draw-
Engineering
manage-
ment
reviews
/ap-
proves
written
changes.
Standard
methods
based
on
analysis
and
test
data
de-
veloped
and
tailored
per
product
needs.
Fully
integrated
program
Marketing-
Engineering
team
interactive
review
process.
Timely
feed-
back.
On-going
series
of
de-
sign
reviews.
Multi-
disciplined
signoff.
Technical
specialists
re-
view
written
changes
to
evaluate
impact
and
approve
as
appropriate.
Latest
state-of-art
inter-
active
design
systems
in
place
with
necessary
support
specialists.
_.
N
::l
....
d
0..
c
n
i=:
0
:::i
.....
0
)>
"'
!fl
c
"";
Ill
:::i
n
Ill
Engineering
tests:
None.
Let
the
user
Engineer
does
One
engineering
Test
of
full-scale
Planned
and
funded
de-
(JI
r+
test
it
for
us.
some
experi-
model
tested
by
out-
hardware.
In-house
velopment
test
programs
DI
""'I
menting
in
the
side
lab.
test
facilities.
Test
New
products
proven
by
::?.
shop.
engineers
on
staff.
factory
and
field
tests.
:i
IO
Control
of
non-
There
aren't
any,
The
factory
The
engineer
is
con-
The
engineer
decides
Material
Review
Board
of
DI
conformances:
everything
goes.
decides
if
it's
sulted
if
it
looks
if
it
is
good
enough.
technical
specialists
c
good
enough.
bad,
but
we
need
dispositions
non-con-
CD
!!!.
it.
formances.
IO
:i
Engineering
Don't
need
any.
The
engineer
The
department
clerk
Records
procedures
Engineering
records
are
)>
records:
Keep
it
in
our
heads.
keeps
a
folder
collects
and
files
and
centralized
files
controlled
as
integral
Ul
of
notes
and
the
drawings
and
used
to
control
and
part
of
company
Ul
s::
things
some-
records.
retain
records.
records
management
""'I
DI
where.
program.
:i
n
Management
The
engineering
de-
When a
problem
When a
problem
Management
hires
or
A
planned
program
of
CD
evaluation:
partment
does
its
occurs,
man-
occurs,
manage-
designates
a
internal
audits
by
engi-
"'O
own
thing-and
no-
agement
wants
ment
wants
to
know
knowledgeable
per-
neering
and
other
de-
a
body
notices.
to
know
who
what
went
wrong.
son
to
review
the
partments
conducted
IO
""'I
goofed.
engineering
activ-
regularly.
On-going
DI
ities
every
few
program
of
refinement
3
years.
and
improvement
of
management
processes.
w
14
Introduction
to
Design
Assurance
It's
a
good
idea
to
record
the
conclusions
and
the
basis
for
them
for
each
of
the
areas
examined.
Use
these
notes
in
the
planning
proc-
ess,
and
save
them
for
future
reference
as
the
program
gets
underway.
It's
easy
to
forget
why
certain
actions
were
considered
necessary
as
the
plan
is
implemented
and
often
modified
along
the
way.
1. 5. 2
Think
Big,
Start
Small
Look
down
the
road
to
the
future.
How
far
do
you
want
to
go
with
this?
How
broad
a
program
do
you
eventually
want
to
have?
And
how
soon
do
you
want
to
get
there?
Generally,
a
good
approach
is
to
proceed
initial-
ly
on
a
small
scale.
Select
one
or
two
areas
which
appear
to
be
logical
opportunities
for
improvement.
Concentrate
on
these
and
learn
by
do-
ing.
Don't
dilute
your
effort
by
trying
to
fix
many
things
all
at
once.
That
approach
can
be
both
disruptive
and
ineffective.
When
planning
the
development
of
new
Design
Assurance
methods,
recognize
that
each
organization
must
tailor
its
practices
to
its
own
local
situation.
The
methods
chosen
should
reflect
the
size
and
personality
of
the
company,
the
complexity
of
the
product,
the
competitive
situation.
the
skills
of
the
person
who will
be
affected
by
it,
and any
other
factors
of
significance
to
the
particular
firm.
Some
companies
are
very
rigid,
others
quite
flexible.
Some
are
very
formal,
and
others
informal.
Nevertheless,
to
be
effective,
the
Design
Assurance
measures
chosen
must
be
applied
with
a
degree
of
discipline
and
integrity.
Seek
methods
you
can
live
with
and
then
live
with
them
faithfully.
That
doesn't
mean
you
follow a
rigid
course
into
obvious
chaos
or
disaster.
But
don't
arbitrarily
bend
the
rules
at
every
turn
of
events.
Give
the
process
a
chance
to
work
for
you.
Much
has
been
written
in
the
management
literature
about
the
best
ways
for
introducing
change.
And
most
of
it
applies
to
introducing
new
methods
of
operation,
like
Design
Assurance.
Take
time
to
plan,
and
do
your
homework.
Communicate
your
plans
and
intentions
and
involve
the
people
affected.
Get
more
than
one
input
on
how
to
do
it.
Listen
and
be
responsive
to
questions
and
comments
from
the
people
that
will
be
applying
the
new
methods.
And
put
a
knowlegeable
leader
in
charge
of
making
it
happen.
As a new
method
is
developed,
take
time
to
train
the
persons
that
must
use
it.
It's
not
enough
to
know
what
is
to
be
done
and
how
it
should
be
accomplished.
People
nowadays,
especially
professional
and
administrative
people,
want
to
know
more.
They
want
to
know
why
it
is
to
be
done
this
way
and
what
is
significant
about
this
particular
method.
In
the
long
run,
it
is
very
helpful
and
typically
gives
better
results.
When
people
understand
the
process,
there
is
a
much
greater
probability
that
the
intent
will
be
achieved.
Last
but
not
least,
management
must
then
give
the
persons
assigned
a
reasonable
time
to
develop
and
debug
the
process
so
it
becomes
an
ef-
fective
method
of
operation.
Summary
15
1. 5. 3 Follow-On
Activities
After
the
first
one
or
two
elements
have
been
implemented
success-
fully,
then
select
the
next
couple
of
elements
to
improve.
Use
the
same
care
and
approach
on
the
second
phase
as
was
used
successfully
on
the
first.
Don't
assume
it
will
automatically
happen
now.
In
this
manner,
ease
into
the
program,
and
it
will
provide
benefits
with
the
minimum
of
disruption.
As
the
implementation
of
the
various
program
elements
proceeds,
be
alert
to
the
interaction
of
the
various
elements.
For
instance,
the
new
system
for
controlling
changes
to
drawings
might
also
work
well
for
controlling
changes
to
specifications
or
instruction
manuals.
The
process
for
checking
hand
calculations
might
also
apply
to
verifying
new
or
revised
computer
programs.
Methods
for
filing
and
retaining
design
records
might
also
work
for
test
records.
This
is
often
a
syner-
gystic
process
that
leads
to
further
refinements
and
efficiencies.
As
the
various
elements
of
the
Design
Assurance
program
are
introduced,
management
should
monitor
the
process
and
look
critically
at
the
results.
Management
has
the
right
and
obligation
to
expect
new
methods
to
give
improved
performance
and
do
it
in
a
cost-effective
manner.
Anything
less
should
be
re-examined
and
modified
or
eliminated.
Management
evaluation
is
important
for
several
different
reasons.
First,
to
find
out
if
the
new
method
is
actually
being
used.
Second,
to
determine
if
it
is
giving
the
intended
results.
Third,
is
it
efficient
to
do
it
this
way
in
actual
practice?
Are
there
any
wrinkles
that
need
to
be
ironed
out?
And,
finally,
now
that
people
are.
using
it,
do
they
have
suggestions
for
improving
on
it?
The
evaluation
process
also
conveys
a
message
of
commitment
on
management's
part
to
make
it
work.
Again,
management's
actions
speak
louder
than
its
policies
or
pronouncements.
1.
6
SUMMARY
Design
Assurance
is
an
important
part
of
a
company's
broad
commit-
ment
to
quality.
It
is
the
process
of
applying
sound
engineering
practices
to
all
engineering
tasks.
Furthermore,
it
reflects
manage-
ment's
commitment
to
excellence
in
its
products.
Engineering
manage-
ment
must
take
the
lead
in
determining
the
scope
and
direction
of
the
Design
Assurance
program.
They
must
also
provide
the
necessary
push
to
make
it
happen.
From
there
on,
the
program
should
stand
the
test
of
time.
It
should
be
expected
to
pay
for
itself
in
the
long
run
through
the
prevention
of
problems
and
in
satisfying
real
market
needs.
Anything
less
should
not
be
tolerated
.
